1. Prevalence of spondylarthropathies in HLA-B27 positive and negative blood donors;Braun;Arthritis Rheum,1998
2. Prevalence of ankylosing spondylitis in males and females in a young middle-aged population of Tromso, northern Norway;Gran;Ann Rheum Dis,1985
3. Preliminary core sets for endpoints in ankylosing spondylitis. Assessments in Ankylosing Spondylitis Working Group;Van Der Heijde;J Rheumatol,1997
4. Validity aspects of erythrocyte sedimentation rate and C-reactive protein in ankylosing spondylitis: a literature review;Ruof;J Rheumatol,1999
5. Nonsteroidal antiinflammatory drugs reduce radiographic progression in patients with ankylosing spondylitis;Wanders;Arthritis Rheum,2005